Police arrested five men in northern England on Tuesday in two separate investigations into alleged terrorist offenses, including the disappearance of a suspected terrorist, authorities said.

One inquiry related to the alleged preparation of a terrorist attack and the other to allegations help was given to a terror suspect who fled house arrest, law enforcement officials said.

Two men, aged 25 and 29, who were arrested in Halifax in West Yorkshire, were being transferred to London for questioning, the Metropolitan Police said.

Both were arrested on suspicion of committing, preparing or instigating acts of terrorism, said a police spokeswoman who spoke on condition of anonymity in line with departmental policy.

Unarmed police carried out the arrests and no bomb making materials were recovered in initial searches of four properties in Halifax, 200 miles north of London. Officers were carrying out a related search at an apartment in north London, the spokeswoman said.

In a separate inquiry, Greater Manchester Police said two men, aged 24 and 32, had been arrested in a series of raids in the city. Several houses were being searched and the men were being questioned on suspicion of supporting and facilitating terrorism.

Home Secretary John Reid told lawmakers on Jan. 16 a suspect living in the Manchester area had escaped and had wanted to travel overseas for "terrorism-related purposes."

The man had been supervised under the government's control order program, which is used to hold suspects deemed a national security risk — but not charged with any offense.

Under the scheme, suspects remain under police observation and can be electronically tagged, kept under curfew, denied the use of telephones or the Internet, and are barred from meeting outsiders.

The system was created by Prime Minister Tony Blair's government after Britain's highest court ruled in December 2004 that it was unlawful to detain terrorist suspects indefinitely without trial.

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